Daewoo 710B service manual 6-2. V.OSC/Deflection Circuit, Unstable or Abnormal picture

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6-2. V.OSC/Deflection Circuit

6-2. V.OSC/Deflection Circuit

Unstable or

Abnormal picture

 

 

 

 

Is

No

 

 

 

 

± 13V DC line

 

 

 

 

 

 

 

 

 

correct?

 

 

 

 

 

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Is

 

 

 

 

 

 

45Vp-p

the output

Yes

 

 

 

 

waveform of IC401

 

 

 

 

(pin 6) normal?

 

 

 

 

 

 

No

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Is the

Yes

 

 

 

 

output pulse

 

 

 

 

of IC501 (pin 23)

 

 

 

 

 

normal?

 

 

 

 

 

 

No

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Trouble in V.Sync line

 

 

 

 

 

 

or IC501 failure.

 

 

 

 

 

 

 

 

 

 

Trouble in

power supply unit

V.DY

failure

Trouble in IC401 or its ambient circuit

21

Image 23
Contents XGA COLOR MONITOR Model 710B Service ManualCONTENTS Implosion Protection SAFETY PRECAUTIONSSafety Check Fire & Shock HazardTerms in the manual GENERAL SAFETY INFORMATIONSymbols in the manual Symbols as marked on equipmentGeneral Servicing Precautions SERVICING PRECAUTIONSGeneral Soldering Guidelines Electrostatically Sensitive ES DevicesRemoval IC Removal/ReplacementReplacement “Small-Signal” Discrete Transistor Removal/ReplacementTECHNICAL INFORMATION Power IC, Transistor or Devices Removal/ReplacementDiode Removal/Replacement Abbreviations GENERAL INFORMATIONCaution For Servicing PIN CONNECTORCAUTIONS FOR ADJUSTMENT AND REPAIR ADJUSTMENT KEY OPERATION & ADJUSTMENTBRIGHTNESS ADJUSTMENT PROCESSRECALL CONTRASTOSDOn-Screen Display Menu ROTATION Choose different preset color temperatures or set your own customized Self Diagnosis No Character TROUBLESHOOTING HINTS1. No Character No Raster 2. No RasterOne color is missing 3. A missing ColorAbnormal OSD Font 4. Abnormal OSD FontTrouble in Horizontal output circuit No Raster 5. Horizontal Output Circuitcorrect? Unstable pictureIs H.Sync input pin of IC501Unstable or Abnormal picture 6-2. V.OSC/Deflection CircuitMonitor remains unfocused 7. FocusFocus is poor 7-1. Dynamic FocusPoor convergence 8. Convergence1.Check B+ section of TDA9109 and its ambient circuit 9. Abnormal Picture 9-1. Horizontal SizeAbnormal H.Size changed, is the H.size changed?Abnormal V.Size 9-2. Vertical SizeTrouble in H.V circuit No Raster 10. High Voltage CircuitSide-Pincusion distortion is excessive or barrel 11. Side-Pincushion CircuitTrouble in P.S.U 12. Power Supply Unit P.S.U8.7V DC? of C104 13V DC?13V DC? Main Adjustment ALIGNMENT PROCEDUREStandard Adjustment Conditions Pre-Adjustmentl Repeat e,f,g,h,i,j DIAGRAM Main PCB Component Side PCB LAYOUTMain PCB Solder Side Video PCB Component Side Video PCB Solder Side Page EXPLODED VIEW DIAGRAM Abbreviation of Description REPLACEMENT PARTS LISTImportant Safety Notice PART-DESC CIRCUIT BOARD ELECTRICAL PARTS LISTPART-CODE PART-NAMEPART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-NAME PART-DESC PART-CODEPART-NAME PART-DESC PART-CODEPART-NAME PART-DESC DAEWOO ELECTRONICS CO OVERSEAS SERVICE DEPTServ ce Manual PRINTED DATE NOV.1998